1. Field of the Invention
The present invention relates to an information processing system and, in particular, to a system for diagnosing diagnosed units such as a main storage unit, a system control unit, and executing units which implement the information processing system.
2. Description of the Prior Art
In the prior art, a diagnostic system comprises a diagnostic processor and an interface connected to the diagnostic processor and has been designed for diagnosing those units in a specific information processing system. Those diagnosed units are assigned with different unit numbers. The diagnostic processor delivers a specific one of those unit numbers and a diagnosis indicating data signal to the interface. The interface receives the specific unit numbers and the diagnosis indicating data signal and delivers the diagnosis indicating data signal to those diagnosed units. Upon receiving the diagnosis indicating data signal, the diagnosed units transmit diagnosing data sets to the interface. Then, the interface selects a specific one of the diagnostic data sets from the specific diagnosed unit by reference of the specific unit number and delivers the specific diagnostic data set to the diagnostic processor. Therefore, the diagnostic processor diagnoses the specific diagnosed unit by use of the specific diagnostic data set.
The interface comprises a selector and a plurality of ports which are equal to the number of the diagnosed units. The ports are connected to the diagnostic processor and also connected to the diagnosed units. The ports receive the diagnosis indicating data signal from the diagnostic processor and deliver it to the diagnosed units. The ports are also connected to the selector and deliver the diagnostic data sets from the diagnosed units to the selector. The selector is also connected to the diagnostic processor and receives the specific unit number. The selector selects the specific diagnostic data set from the diagnostic data sets by reference to the specific unit number and delivers the specific diagnostic data set to the diagnostic processor.
Since the known diagnostic system is designed adaptable for a specific information processing system, it cannot be used for diagnosing another information system having a different number of diagnosed units. For example, the diagnostic system cannot diagnose an increased number of diagnosed units in the other information processing system.